Al wrote:
I have a 30s house with some rubber-coated wiring.
Before replacing this, I'm going to put in a new consumer unit.
Before doing that, I'd like to ask a couple of questions.

My problem:
There is no consumer fuse - tails go straight from the supply cable to
the meter.
From the meter, the tails go to a small junction box (would this be a
"Henley" block?).
Tails then go from the junction box to the consumer unit.
My plan is to carefully remove the old consumer unit tails from the
live terminals using an insulated screwdriver, then fit new consumer
unit and new tails.

My other problem:
The current wiring would not pass any sort of inspection, and I'm not
expecting to finish the rewiring very soon.

Q1: Who owns the junction box?
It is after the meter, but is sealed with wire and (old looking) lead
crimps. That might mean something official, or might be to discourage
me from the above dangerous manouver.

Q2: What exactly is inside the junction box?
Bakelite box, about 4" x 3". The meter tails enter on the bottom-right
one in front of the other (ie in a plane perpendicular to the wall)
and the consumer unit tails exit on the bottom-left, similarly one in
front of the other.

Thanks, Al.

Your procedure sounds high risk to me.
There should be a fuse on the incoming, maybe you haven't found it yet.
I'd ring your elec supply company and ask them to fit one pronto if there
isn't.
The only downside of this is they may well condemn your wiring if they see
it.

AFAIK the junc box after the meter is yours to do with what you like.
What the elec companys do care about is any tampering with the meter seals.
They don't seem to care if you remove those on the fuse before it.